Description:
------------
IntlDateFormatter::parse() does not change $position argument

https://3v4l.org/i1mPA

Regression was probably introduced by this commit: https://github.com/php/php-src/commit/40ecad34022b6e687cc654d47c88f8cef5d418f

Test script:
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<?php

$formatter = new IntlDateFormatter("en-GB", IntlDateFormatter::NONE, IntlDateFormatter::NONE, 'UTC', null, 'yyyy-MM-dd');
$position = 0;
$parsedDate = $formatter->parse("2017-10-12", $position);
var_dump($parsedDate, $position);

Expected result:
----------------
The 2nd argument $position which is passed by reference will contain the position at which parsing ended. It works as expected before 7.2.0alpha2

Actual result:
--------------
Always 0. See 3v4l results